Member Advice on Cavity Wall Insulation

I decided to have cavity wall insulation installed early in 1997 after seeing an advertisement in our local paper offering a £200 grant towards the cost. Our house was built around 1930 and is an end terrace, thus having three external walls, so I thought cavity wall insulation would be a good investment and I was right!

I contacted the firm recommended in the advertisement, Heatsavers Insulation Limited, who came and did a survey of my house. They asked questions about the house – any problems with damp, availability of access etc. and offered me a quote of £479 less the £200 grant applicable. I paid a deposit of £79 and arranged a date for the work to be done.

They came on 20th March 1997 and took less than half a day to install the insulation. To do this they drilled small holes in the external walls, pumped the InstaFibre into the cavity through the holes and then refilled the holes. There was a small area on the back of the house that was out of reach because of our conservatory so they had to drill a couple of holes in the internal walls. Even this was no problem as they were refilled neatly and I just repainted the area.

InstaFibre is a blown mineral wool that works by storing the heat in the inner wall and radiating it back into the room, meaning that you can turn down your heating and still remain warm. It also eliminates draughts by sealing the gaps around the doors and windows.

InstaFibre is fully approved by the BBA (British Board of Agrement) who is the watchdog for building products. It is non combustible, allows the walls to breathe, will not transmit the passage of water or sustain the growth of mould, will not settle or escape from the walls, and will remain effective for the life of the building.

It is manufactured from natural products and does not have any chemicals added to it during the installation process. It is ozone friendly with no CFC’s or chemical vapours.

The whole thing is covered by a 25 year guarantee which will be passed on with the house should we sell.

I have really noticed a difference in both the temperature of the house and the cost of the central heating since it has been done. The house itself is appreciably warmer especially upstairs where we don’t have many radiators. I keep records of average usage for all utilities and the average daily usage of gas before the cavity wall insulation was just over 2 units per day for the winter quarter. The average usage is now barely 1.5 units per day, which represents a fall in usage of about 25%.